1. Field of Invention
Embodiments of the invention relate generally to electronic devices and, more specifically, in certain embodiments, to asymmetric fin transistors.
2. Description of Related Art
In many types of electronic devices, transistors are used to selectively conduct current. The transistors usually include a source, a drain, and a gate. The gate controls current flowing between the source and the drain. Transistors are often characterized by a threshold gate voltage, below which the transistor is considered to be in an off state, and above which the transistor is considered to be in an on state. Thus, to impede the flow of current when the transistor is off, the gate voltage of the transistor is held below the threshold voltage. However, some transistors function in the opposite manner-conducting current at a sub-threshold gate voltage and impeding current at a higher gate voltage.
When a transistor is in the off state, some current may still leak. Electric fields within the transistor may form conductive paths through which current escapes. Often when the transistor is off, the gate voltage is different from the drain voltage. This voltage difference may form a relatively strong electric field, as a portion of the gate is frequently disposed near part of the drain. The resulting electric field can cause charge carriers to flow between the drain and the substrate on which the transistor is formed, a phenomenon referred to as “gate-induced drain leakage” (GIDL).